Texas Instruments TMS320C28x, Reference Manual

Page: 75 / 695

Shift Operations
2-45 Central Processing Unit
Table 2 − 11. Shift Operations
Operation Type Illustration
Left shift of 16-bit value for ACC
operation.
Syntaxes:
ADD ACC, loc16 << 0...16
ADD ACC, # 16Bit << 0...15
ADD ACC, loc16 <<T
SUB ACC, loc16 << 0...16
SUB ACC, # 16Bit << 0 ...15
SUB ACC, loc16 << T
MOV ACC, loc16 << 0...16
MOV ACC, # 16Bit << 0...15
MOV ACC , loc16, << T
Shift left
0
16-bit value to 16 LSBs
0/Sign
32 bits to ALU
SXM
Store 16 LSBs of left-shifted ACC.
Syntax:
MOV
loc16 , ACC << 1...8
Shift left
0
ACC
16 LSBs to ALU
Discard
Store 16 MSBs of left-shifted ACC.
Syntax:
MOVH
loc16 , ACC << 1...8
Note: This instruction performs a single
right shift by (16
− shift1 ), where shift1 is a
value from 0 to 8.
Shift right
ACC
16 LSBs to ALU
Discard
Logical left shift of ACC. The last bit to
be shifted out fills the carry bit (C).
Syntaxes:
LSL ACC,
1...16
LSL ACC, T (shift = T(3:0))
LSL ACC, T (shift = T(4:0))
Note: If T(3:0) = 0 or T(4:0) = 0, indicating
a shift of 0, C is cleared.
Shift left
0
ACC
32 bits to ACC
C
Last
bit out
Discard
other bits